6. Oneok
6. Oneok
Fortune 500 rank: 175
2011 revenue: $15.1 billion
2011 total shareholder return: 61.3%
Ticker: OKE

Shares of Oneok, a Tulsa, OK-based pipeline company, hit a record high when it announced it was leaving the retail marketing business by selling a subsidiary. In December, Oneok reached an agreement to sell the division to Constellation Energy Group for approximately $22.5 million. Shares were already up after executives announced in November that 2011 net income would beat their initial projections.

Investors are now focused on Oneok's plans to build its first oil pipeline. The $1.8 billion project is expected to bring hundreds of thousands of barrels of crude a day from North Dakota's Bakken Shale field to an oil-trading hub in Cushing, Oklahoma.

By Nin-Hai Tseng - Last updated May 07 2012: 10:52 AM ET